<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            border: 15px solid red;
            /* border-top-width: 51px;
            border-right-width: 38px;
            border-bottom-width: 20px;
            border-left-width: 132px; */
            /* border-right: 1px solid red;
            border-bottom: 1px solid red;
            border-left: 1px solid red; */
        }
        /* 边框宽度 就是边框图片宽度 */
    </style>
</head>
<body>
    <div>1</div>
</body>
</html>